Electric contact breaker



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April 24, 1951 A. 'rERUzzl ELECTRIC .CONTACLBREAKER 3 Sheets-Sheet 1Filed Jan. 11, 1947 NQ l \D\ I n MNHN m, u Q .Hd sm W .Hu SAWV ,w QV...n s@ ma R -l i uw m n v Il l Il s m uw w vi ON len w 'l I. b l l 1 sm wv N F @MMT y April 249 195i A. TERUzzl ELECTRIC coNTAcTBREAKER 3Sheets-Sheet l 2 Filed Jan. ll, 1947 Apri 249 195i A. Tl-:Ruzznv2,55),623

i ELECTRIC CONTACT-BREAKER Filed Jan. 11, 1947 3 Sheets-Sheet 5 PatentedApr. 24, 1951 ELECTRIC CONTACT BREAKER.

Angelo Teruzzi, Milan, Italy Application January 11, 1947, Serial No.721,551 In Italy April 13, 1942 Section 1, Public Law 690, August 8,1946 Patent expires April 13, 1962 4 Claims. (Cl. 20G- 153) Thisinvention relates to electric switches and has vspecial reference toContact makers and breakers, change-over switches and the like.

One important object of this invention is to provide an improvedarrangement of the cir-v cuit closing elements of such a switch wherebylto ensure close engagement between the xed contacts and the movablecontacts of such switches.

`A second important object of the present invention is to provide anovel construction of switch wherein, a blade or lever carrying themovable contact is floatingly fulcrumed at the end remote from themovable contact.

A third important object of this invention is to provide a novel formvof switch having such a oating lever with means whereby the contact endof the lever is moved to bring the contact carried thereby intoengagement with a iixed contact and there firmly hold it. A fourthimportant object of this invention is to provide a change-over switchhaving the foregoing characteristics wherein novel arrangements areutilized to prevent closing of both sides' of the switch simultaneously.

With the above and other'lobjects in view, as will be presentlyapparent, the invention consists in general of certain novel details ofconstruction, and combinations of parts hereinafter fully described,illustrated in the accompanying drawings and particularly claimed.

In the drawings like characters of references indicate. like partsthroughout the views, and:

Fig. 1 is a longitudinal section of a changeover switch constructed inaccordance with this invention.

Fig. 2 is a view, partly in section and partly in elevation and showinga lever actuated switch constructed in accordance with the invention.

Fig. 3 is a view similar tol Fig. 2, but showing a modification thereof.

Fig. 4 is a view similar to Fig. 2, but showing a second modificationthereof. Y y K In the form of the invention shown in Fig. 1, there isdisclosed a base B on which is mounted 'a housing H carrying a cap C.Extending through the center of the base B is abinding post P carryingat its upper end acontact plate 9a whereon is mounted a pair of spacedxed contacts 9. At each end of the base is shown, at PI and P2respectively, a binding post similar to the binding post P. To each` ofthe posts PI and P2 is attached one end of a C-type leaf spring I3 andthe other endofeach spring I3 isattachedto a lever or bladell adjacentone vlug 8a from the fulcrum surface IQ.

end thereof. Projecting upwardly from the bas B are ribs |901. eachhaving a downwardly facing notch I9 which receives a lug 8a formed onthe end of the blade 8 adjacent the attachment of the spring I3. Thearrangement just described forms,`under certain conditions of operationt0 be presently explained, fulcrum means for theblades 8. At theopposite end of each Ablade 8 is a contact button 8b forming the movablecontacts for engagement with contacts 9. Supported in the housing H arepivot pins 5 and on each of the pins 5 is mounted a rocking lever 4having on its under side a notch 6. In each notch 6 is mounted the upperend of a push link 'I the lower end of which engages in a V-shapeddepression 8c formed at about the center of the blade 8. Beneath eachblade 8 is a coiled compression spring I2 which is seated at its lowerend in the base B and bears at its upper end against the blade to urgethe latter upwardly and thus to normally keep the lug 8a fulcrumed inthe notch I9 as shown at the right side of Fig. 1. In one arm of eachlever 4 is formed a slot fia.r wherein engages a pin 4b carried by arespective pushbutton I and 2 extending through the cover C.

In the operation of the device as thusfar described the fully openposition of the switch is the same at both sides of Fig. 1 as is shownat the right of that figure in which position the lug 8d will fulcrum inthe notch IS and the contacts 8b will be in separated positions. Nowletit be supposed it is desired to close contact between lines connectedto the binding posts P and P2. The push button 2' is depressed whichcauses the pin 4b to rock the lever on the fulcrum pin 5. This causesthe upper end oi the link 1 to swing to the right and primarily effectsclosing of the left hand contact 8b on the corresponding contact 9. Atthis instance the pushbutton 2 has not been fully depressed and theupper end of the link 'I still lies to the left of a lvertical linethrough the center of the bottom end of this link. The final movementdownwardly of the button 2 swings the upper part of the link 'i to theright of the vertical line and thus beyond the dead center and at thesame time frees the In order to hold the contacts closed and the lever 4and link 'I in the position shown at the left of Fig. 4, each of thelevers 4 has an arm lc extending in the opposite direction to theslotted arm and this larm is provided with a lug or boss 4d at itsextremity which, with the lever 4 in circuit closing position, engages"the slotted bottom-'end I6 of a Centrally disposed push button 3. Itwill now be seen that upon depression of the button 3 opposite to whichit was rocked by depression of the button 2 will rst permit rulcrumingof the lug 8a in the fulcrum notch I9 and then separation of the contact8b from the contact 9.

In a change-over switch it is of course undesirable that both sides ofthe switch should be connected to the center and to prevent such anoccurrence in the present switch the following means are used. Alinedbelow the center of the button 3 is a pin 20 on which is rockinglymounted an arm I1 the upper end of which engages in the slotted end I5of the button 3. The arm Il has at opposite points of its side edge camlike projections I4 and I5 and the distance between the extreme pointsof these projections is such that the arm II is swung from one side toanother as the respective lever 4 is swung to a circuit closingposition. When thus one lever 4 is in circuit closing position the lug4d of the other lever 4 will be engaged by the side of the arm I'I belowthe camining point. Consequently, as shown at the right of Fig. l thebu,ton of the open side of the switch cannot be pushed and closing orthe open side of the switch cannot be effected.

In the form of the invention shown in Fig. 2 there is provided a base 6Gwhereon is mounted a pair of spaced binding posts 48 and 58. The post 48carries a. plaie 50 whereon is mounted a iixed contact 46. A C-type leafspring 56 has one end connected to the binding post 53 and its other endconnected adjacent one end of a compound blade comprising an upper leaf40 and a lower lleaf 42 rmly pointed together. The leaf 2 carries at oneend a lug 4I engaging in the fulcrum notch of a rib 54 which extendsupwardly from the base G0. rlhe leaf 4B has a centrally disposedinverted V-shaped bend i3 extending upwardly from the end positions ofthis leaf. The remaining end of the lea-f di has a contact 45 fixedthereto and engaging upon closing of the switch on the contact 45.Extending upwardly from the base 6I) is a rib S2 in which is rota.ablymounted a shaft (not shown) having a square end 34. On the end 34 isfixed a hub 35 from which projects radially a cam 3S the extremityofwhich is notched as at 3l to receive the apex of the projection 43 uponclosing of the switch. The shaft carrying the hub 35 is rotated by alever 32 provided with a hand knob 30 on its free end. A spring 52corresponds to spring I2 of Fig. l. The position of the switch whenclosed is here shown in full lines and when opened in broken. Theoperations of closing and biassing of the cam 38 eiect the blades, theiixed and movable contacts and the blade fulerum as in the form shown inFig. 1.

In the form shown in Figs. 3 and 4 there is provided a base a having atransverse grooved portion 68o. This base carries the binding posts 48and 5B. These forms also have the C-type spring 55, coiled spring 52 andarm 58, fixed contact and notched member 54 as in the forni shown inFig. 2.

In the form shown 3 there is provided blade l2 having an upwardly bentcamming portion 'I3 provided at its apex with a depression T311. Thisblade has the lug 4I and contact 44 as in Fig. 2. For the operation ofthe blade in this form there is provided a lever 64 having a journal 58projecting from its lower end and seated in the groove of the portion60o. Projecting from the lever 54 above the blade 'I2 is a boss 'l0which in operation rides along the cam 'I3 and, upon the switch beingclosed, seats in the depression 13a. In order to limit swinging movementof the lever, arms 64a project laterally from the upper part of thelever and selectively engage stops 64b carried by the base as the levermoves between the full line switch closing position and the broken lineshowing of the parts with the switch open position.

In the form shown in Fig. 4 the blade 80 is of the same type as theblade 8 of Fig. l. The operating lever Q4 is like that shown in Fig. 3except that the boss i0 is replaced by a pin 'I6 whereon is mounted ahub 'I4 having an arm 75 projecting tangentially therefrom and havingits free end engaging in the bottom of the V-shaped portion of the bladeSi). The open and closed positions of the different elemenls of thisform are clearly shown by the broken and full line representations ofthe moving parts.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is:

l. In an electric switch, a. iixed contact having means for connectionto a conductor, a blade carrying' at one end a contact movable into andout of engagement with said iixed contact and having means forconnection to a conductor, a fixed fulcrum against which the oppositeend of said blade is detachably engaged, a spring engaging the bladeintermediate its ends and normally holding the blade in engagement withsaid fulcrum and said contacts out of engagement, and actuating meansoperable to move said blade to bring the contact thereon primarily intoengagement with the fixed conLact and thereinafter move said blade outof engagement with said fulcrum.

2. In an electric switch, a fixed contact having means for connection toa conductor. a blade carrying at one end a contact movable into and outof engagement with said fixed contact and having means for connection toa conductor, a fixed fulcrum against which the opposite end of saidblade is detachably engaged, a spring engaging the blade intermediateits ends and normally holding the blade in engagement with said fulcrumand said contacts out of engagement, said spring engaging said bladeadjacent said fulcrum and spaced from the fulcrum supported end thereof,and operating means operating against said spring and engaging the bladebetween the location of the spring engagement and the blade supportedContact.

3. In an electric switch, a fixed contact having means for connection toa conductor, a blade carrying at one end a contact movable into and outof engagement with said iixed contact and having means for connection toa conductor, a fixed fulcrum against which the opposite end of saidblade is detachably engaged, a spring engaging the blade intermediateits ends and normally holding the blade in engagement with said fulcrumand said contacts out of engagement, said spring engaging said bladeadjacent said fulcrum and spaced from the fulcrum supported end thereof,and operating means operating against said spring and engaging the bladebetween the location of the spring engagement and the blade supportedcontact, said operating means including a rotatable camming arm an meansto rotate the Same.

4. In an electric switch, a fixed contact having means for connection toa conductor, a b'iade carrying at one end a contact movable into and outof engagement with said fixed contact and having means for connection toa conductor, La'

xed fulcrum against which the opposite end of said blade is detachablyengaged, a spring en- I gaging the blade intermediate its ends andnormally holding the blade in engagement with said fulcrum and saidcontacts out of engagement,

said spring engaging said blade adjacent saidV fulcrum and spaced fromthe fulcrum supported end thereof, and operating means operating againstsaid spring and engaging the blade be;- tween the location of the springengagement and the blade supported Contact, said operating 15 23951517means including a rotatable camming arm and means to rotate the samesaidblade having an oiset portion Wherewith Vsaid arm lockingly engages.

ANGELO TERUZZI.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,239,833 Singer Sept. 11, 19172,262,306 Thompson Nov. 11, 1941 Meuer Sept. 8, 1942

